How well does BLD (brake lock differential) really work?

WXman

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All I know is that when I had my 2012 JKU I went on some trails with a 2008 JKU (prior to BLD becoming standard) and I walked up some off-camber hills with ease that he could only do with a running start and momentum.

I've had LSD diffs and I've installed lockers, but in my opinion the BLD system that's standard on Wrangler is just about all that 95% of owners will ever need. If you're doing serious fourwheeling, then lockers are great. But for the average trail, they aren't needed.
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86CJ7

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With the anti-slip package you also get a D44 rear end. Its a heck of a deal for the package
-lsd
-d44
-all terrain tires
If you purchase a JL Sport with a manual trans you get the D44 rear end. Do you also automatically get the LSD? i.e. don't all D44's come with LSD?
 

JLUin818

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If you purchase a JL Sport with a manual trans you get the D44 rear end. Do you also automatically get the LSD? i.e. don't all D44's come with LSD?
Not sure if Sahara has d44 option and rubicon with d44 does not come with one
 

cdan

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My opinion in simplistic terms:
  1. BLD is better than either locker or LSD in snow and on ice
  2. BLD is almost as good as locker, and equal to LSD in mud
  3. BLD is not as good as LSD or locker in rocks
At this time if you don't have the 44 rear differential, and you don't, there isn't a LSD or locker available.
 

D60

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At this time if you don't have the 44 rear differential, and you don't, there isn't a LSD or locker available.
Well now, there's always a Lincoln Locker ;) Just kidding! (but technically true)
 

lightsout

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At this time if you don't have the 44 rear differential, and you don't, there isn't a LSD or locker available.

For fun I was having some work done at 4WP I asked about Lockers for my Sahara they quoted me $2200 out the door installed. However for that you can buy Rubi take offs
 

SecondTJ

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In a situation where you would go mudding and assuming you have LSD in the rear, would it be best to turn off traction control/BLD? Would BLD be best used on the road and rock crawling and turning it off for mudding and sand?
BLD will help you more than LSD. The factory clutch based LSD is not very effective off road

  1. BLD is not as good as LSD or locker in rocks
LSD is useless in the rocks
 
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Boatbuilder88

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According to Jeep... Trac-Lok anti-spin (limited slip differential) is always active and works independently of BLD. BLD works with both axles but is only active in 4-Hi and 4-Lo. BLD will kick in if the torque bias is higher than Trac-Lok can handle.
 

Hayseed_JLUR

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BLD works great - but it does have its limitations as people have stated,
 

JimLee

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If you purchase a JL Sport with a manual trans you get the D44 rear end. Do you also automatically get the LSD? i.e. don't all D44's come with LSD?
No. I have a sport that came with a D44 rear and an open differential (auto trans). I didn't care when I bought it as I plan on replacing both axles anyway. BLD has worked just fine for me so far while I'm waiting to buy my aftermarket axles, in sand, up steep trails with loose gravel, and up rock obstacles with water running down them. Honestly I haven't found anything that can stop my Sport with a 2.5 RK lift and 35's yet, although I haven't tried to find anything super challenging either, just takled what's in my way to get where I'm going. I have a winch in case of emergency but it hasn't been needed yet although it's nice to have the confidence that its there if you need it.
 

Renhilio

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Not to resurrect an older thread but.. not one comment on the dude in that video writing on his hood with a marker surprises me.
 
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